Intangible Assets (Schedule of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Sep. 30, 2012
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 154,939	$ 154,644
Accumulated amortization	(53,331)	(48,749)
Net carrying amount	101,608	105,895
Trade name and trademarks
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	3,143	3,125
Accumulated amortization	(1,008)	(878)
Net carrying amount	2,135	2,247
Technology
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	25,422	25,396
Accumulated amortization	(19,018)	(18,093)
Net carrying amount	6,404	7,303
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	126,374	126,123
Accumulated amortization	(33,305)	(29,778)
Net carrying amount	$ 93,069	$ 96,345